Typically, magnetic thin films are first deposited using ultrahigh vacuum physical vapour deposition techniques such as magnetron sputtering and ion beam deposition.[1]}, [2]}, [3]}, [4]}, [5]} Next, nanostructure and device patterns can be defined using electron beam lithography (EBL) and subsequently transferred using ion beam etching.[2]}, [3]}, [5]} Meanwhile, a self-assembled block copolymers (BCP) technique can be utilized to study high throughput patterning of magnetic nanowire arrays.[1]}, [10]}, [11]} By using a carbon hard-mask patterned by a self-assembled polystyrene-block-poly(2/4-vinylpyridine) and polystyrene-blockpolydimethylsiloxane (PS-b-PDMS) diblock copolymer mask, we fabricated highly scalable, periodic nanowire arrays of sub-50 nm pitch and wire widths.
